Firestone Coil Rite Air Spring Bag Model 4160 CR 4160 COIL-RITE
[F039-4160]

Coil-Rite™ air helper springs mount inside an existing open coil spring suspension. These air springs provide adjustable spring rates far superior to the standard coil spring. The durable polyurethane air springs will support 500-1,000 lbs per set*.
Coil-Rite air helper springs are made of durable polyurethane to withstand the rigors of coil-sprung suspensions.

Fits:
05-08 F-250 Over 8500 GVWR (4x4 only)
06-08 F-350 (4x4)
05 F-350 (4x2, 4x4)
05-08 F-350 (4x2, 4x4)
05-08 F-450 (4x2, 4x4)
05-08 F-550 (4x2, 4x4)